1. Field
The described technology generally relates to display devices; particularly, to the organic light emitting display devices and to methods of operating those display devices.
2. Description of the Related Technology
An active matrix organic light emitting display device can be driven with analog or digital driving method. While the analog driving method produces grayscale using variable voltage levels corresponding to input data, the digital driving method produces grayscale using variable time duration in which an organic light emitting diode emits light. The analog driving method is difficult to implement because it requires a driving integrated circuit (IC) that is complicated to manufacture if the display is to have a large size and high resolution. The digital driving method, on the other hand, can readily accomplish the required high resolution through a simpler IC structure. Also, the digital driving method uses on and off states of a driving thin film transistor (TFT) which is seldom influenced by image quality deterioration due to TFT characteristics deviation. Therefore, digital driving methods are useful for a large panel display.
However, with digital driving, since pixels do not continuously emit light during one frame, and repeat the light emission and non-emission, a dynamic false contour, that does not exist in a real image, can occur as a viewer scans across a moving image.